diff --git a/ui/dialog.go b/ui/dialog.go
index 21d3afd..7f26ed4 100644
--- a/ui/dialog.go
+++ b/ui/dialog.go
@@ -17,6 +17,7 @@ import (
 	"github.com/gcla/gowid/widgets/text"
 	"github.com/gcla/termshark/v2"
 	"github.com/gcla/termshark/v2/widgets/appkeys"
+	"github.com/gcla/termshark/v2/widgets/minibuffer"
 )
 
 //======================================================================
@@ -27,6 +28,7 @@ var (
 	hmiddle    gowid.HAlignMiddle
 	vmiddle    gowid.VAlignMiddle
 	YesNo      *dialog.Widget
+	MiniBuffer *minibuffer.Widget
 	PleaseWait *dialog.Widget
 )
 
diff --git a/ui/lastline.go b/ui/lastline.go
new file mode 100644
index 0000000..12f94c9
--- /dev/null
+++ b/ui/lastline.go
@@ -0,0 +1,223 @@
+// Copyright 2019-2020 Graham Clark. All rights reserved.  Use of this source
+// code is governed by the MIT license that can be found in the LICENSE
+// file.
+
+// Package ui contains user-interface functions and helpers for termshark.
+package ui
+
+import (
+	"fmt"
+	"strconv"
+
+	"github.com/gcla/gowid"
+	"github.com/gcla/gowid/gwutil"
+	"github.com/gcla/termshark/v2"
+	"github.com/gcla/termshark/v2/widgets/minibuffer"
+)
+
+//======================================================================
+
+var notEnoughArgumentsErr = fmt.Errorf("Not enough arguments provided")
+
+type minibufferFn func(gowid.IApp, ...string) error
+
+func (m minibufferFn) Run(app gowid.IApp, args ...string) error {
+	return m(app, args...)
+}
+
+func (m minibufferFn) OfferCompletion() bool {
+	return true
+}
+
+func (m minibufferFn) Arguments([]string) []minibuffer.IArg {
+	return nil
+}
+
+type quietMinibufferFn func(gowid.IApp, ...string) error
+
+func (m quietMinibufferFn) Run(app gowid.IApp, args ...string) error {
+	return m(app, args...)
+}
+
+func (m quietMinibufferFn) OfferCompletion() bool {
+	return false
+}
+
+func (m quietMinibufferFn) Arguments([]string) []minibuffer.IArg {
+	return nil
+}
+
+//======================================================================
+
+type boolArg struct {
+	arg string
+}
+
+var _ minibuffer.IArg = boolArg{}
+
+func (s boolArg) OfferCompletion() bool {
+	return true
+}
+
+// return these in sorted order
+func (s boolArg) Completions() []string {
+	return []string{"false", "true"}
+}
+
+//======================================================================
+
+type onOffArg struct {
+	arg string
+}
+
+var _ minibuffer.IArg = onOffArg{}
+
+func (s onOffArg) OfferCompletion() bool {
+	return true
+}
+
+// return these in sorted order
+func (s onOffArg) Completions() []string {
+	return []string{"off", "on"}
+}
+
+//======================================================================
+
+type unhelpfulArg struct {
+	arg string
+}
+
+var _ minibuffer.IArg = unhelpfulArg{}
+
+func (s unhelpfulArg) OfferCompletion() bool {
+	return false
+}
+
+// return these in sorted order
+func (s unhelpfulArg) Completions() []string {
+	return nil
+}
+
+//======================================================================
+
+type setArg struct {
+	arg string
+}
+
+var _ minibuffer.IArg = setArg{}
+
+func (s setArg) OfferCompletion() bool {
+	return true
+}
+
+// return these in sorted order
+func (s setArg) Completions() []string {
+	return []string{
+		"auto-scroll",
+		"copy-command-timeout",
+		"dark-mode",
+		"disable-shark-fin",
+		"packet-colors",
+	}
+}
+
+//======================================================================
+
+func stringIn(s string, a []string) bool {
+	for _, s2 := range a {
+		if s == s2 {
+			return true
+		}
+	}
+	return false
+}
+
+func parseOnOff(str string) (bool, error) {
+	switch str {
+	case "on", "ON", "On":
+		return true, nil
+	case "off", "OFF", "Off":
+		return false, nil
+	}
+	return false, strconv.ErrSyntax
+}
+
+type setCommand struct{}
+
+var _ minibuffer.IAction = setCommand{}
+
+func (d setCommand) Run(app gowid.IApp, args ...string) error {
+	var err error
+	var b bool
+	var i uint64
+	if len(args) == 3 {
+		switch args[1] {
+		case "auto-scroll":
+			if b, err = parseOnOff(args[2]); err == nil {
+				AutoScroll = b
+				termshark.SetConf("main.auto-scroll", AutoScroll)
+				OpenMessage(fmt.Sprintf("Packet auto-scroll is now %s", gwutil.If(b, "on", "off").(string)), appView, app)
+			}
+		case "copy-command-timeout":
+			if i, err = strconv.ParseUint(args[2], 10, 32); err == nil {
+				termshark.SetConf("main.copy-command-timeout", i)
+				OpenMessage(fmt.Sprintf("Copy command timeout is now %ds", i), appView, app)
+			}
+		case "dark-mode":
+			if b, err = parseOnOff(args[2]); err == nil {
+				DarkMode = b
+				termshark.SetConf("main.dark-mode", DarkMode)
+			}
+		case "disable-shark-fin":
+			if b, err = strconv.ParseBool(args[2]); err == nil {
+				termshark.SetConf("main.disable-shark-fin", DarkMode)
+				OpenMessage(fmt.Sprintf("Shark-saver is now %s", gwutil.If(b, "off", "on").(string)), appView, app)
+			}
+		case "packet-colors":
+			if b, err = parseOnOff(args[2]); err == nil {
+				PacketColors = b
+				termshark.SetConf("main.packet-colors", PacketColors)
+				OpenMessage(fmt.Sprintf("Packet colors are now %s", gwutil.If(b, "on", "off").(string)), appView, app)
+			}
+		}
+	} else {
+		err = notEnoughArgumentsErr
+	}
+
+	if err != nil {
+		OpenMessage(fmt.Sprintf("Error: %s", err), appView, app)
+	}
+
+	return err
+}
+
+func (d setCommand) OfferCompletion() bool {
+	return true
+}
+
+func (d setCommand) Arguments(toks []string) []minibuffer.IArg {
+	res := make([]minibuffer.IArg, 0)
+	res = append(res, setArg{})
+
+	if len(toks) > 0 {
+		onOffCmds := []string{"auto-scroll", "dark-mode", "packet-colors"}
+		boolCmds := []string{"disable-shark-fin"}
+		intCmds := []string{"disk-cache-size-mb", "copy-command-timeout"}
+
+		if stringIn(toks[0], boolCmds) {
+			res = append(res, boolArg{})
+		} else if stringIn(toks[0], intCmds) {
+			res = append(res, unhelpfulArg{})
+		} else if stringIn(toks[0], onOffCmds) {
+			res = append(res, onOffArg{})
+		}
+	}
+
+	return res
+}
+
+//======================================================================
+// Local Variables:
+// mode: Go
+// fill-column: 110
+// End:
diff --git a/ui/messages.go b/ui/messages.go
index 55e83c2..b625359 100644
--- a/ui/messages.go
+++ b/ui/messages.go
@@ -69,6 +69,7 @@ A wireshark-inspired tui for tshark. Analyze network traffic interactively from
 't'   - In bytes view, switch hex ⟷ ascii
 '+/-' - Adjust horizontal split
 '</>' - Adjust vertical split
+':'   - Last line mode (minibuffer)
 '?'   - Display help
 
 In the filter, type a wireshark display filter expression.
diff --git a/ui/ui.go b/ui/ui.go
index 1295545..db7375d 100644
--- a/ui/ui.go
+++ b/ui/ui.go
@@ -56,6 +56,7 @@ import (
 	"github.com/gcla/termshark/v2/widgets/filter"
 	"github.com/gcla/termshark/v2/widgets/hexdumper2"
 	"github.com/gcla/termshark/v2/widgets/ifwidget"
+	"github.com/gcla/termshark/v2/widgets/minibuffer"
 	"github.com/gcla/termshark/v2/widgets/resizable"
 	"github.com/gcla/termshark/v2/widgets/rossshark"
 	"github.com/gcla/termshark/v2/widgets/withscrollbar"
@@ -938,6 +939,72 @@ func reallyQuit(app gowid.IApp) {
 	YesNo.Open(appView, units(len(msgt)+20), app)
 }
 
+func lastLineMode(app gowid.IApp) {
+	MiniBuffer = minibuffer.New()
+
+	MiniBuffer.Register("quit", minibufferFn(func(gowid.IApp, ...string) error {
+		// Delay because when control returns to the minibuffer, it closes itself
+		// if there is no error, but that has the side effect of closing this
+		// dialog too :-(
+		app.Run(gowid.RunFunction(func(app gowid.IApp) {
+			reallyQuit(app)
+		}))
+		return nil
+	}))
+
+	// force quit
+	MiniBuffer.Register("q!", quietMinibufferFn(func(gowid.IApp, ...string) error {
+		QuitRequestedChan <- struct{}{}
+		return nil
+	}))
+
+	MiniBuffer.Register("help", minibufferFn(func(gowid.IApp, ...string) error {
+		app.Run(gowid.RunFunction(func(app gowid.IApp) {
+			OpenTemplatedDialog(appView, "UIHelp", app)
+		}))
+		return nil
+	}))
+
+	MiniBuffer.Register("?", quietMinibufferFn(func(gowid.IApp, ...string) error {
+		app.Run(gowid.RunFunction(func(app gowid.IApp) {
+			OpenTemplatedDialog(appView, "UIHelp", app)
+		}))
+		return nil
+	}))
+
+	MiniBuffer.Register("convs", minibufferFn(func(gowid.IApp, ...string) error {
+		app.Run(gowid.RunFunction(func(app gowid.IApp) {
+			openConvsUi(app)
+		}))
+		return nil
+	}))
+
+	MiniBuffer.Register("streams", minibufferFn(func(gowid.IApp, ...string) error {
+		app.Run(gowid.RunFunction(func(app gowid.IApp) {
+			startStreamReassembly(app)
+		}))
+		return nil
+	}))
+
+	MiniBuffer.Register("capinfo", minibufferFn(func(gowid.IApp, ...string) error {
+		app.Run(gowid.RunFunction(func(app gowid.IApp) {
+			startCapinfo(app)
+		}))
+		return nil
+	}))
+
+	MiniBuffer.Register("clear", minibufferFn(func(gowid.IApp, ...string) error {
+		app.Run(gowid.RunFunction(func(app gowid.IApp) {
+			reallyClear(app)
+		}))
+		return nil
+	}))
+
+	MiniBuffer.Register("set", setCommand{})
+
+	minibuffer.Open(MiniBuffer, appView, ratio(1.0), flow, app)
+}
+
 //======================================================================
 
 // getCurrentStructModel will return a termshark model of a packet section of PDML given a row number,
@@ -1404,6 +1471,8 @@ func appKeyPress(evk *tcell.EventKey, app gowid.IApp) bool {
 		app.Sync()
 	} else if evk.Rune() == 'q' || evk.Rune() == 'Q' {
 		reallyQuit(app)
+	} else if evk.Rune() == ':' {
+		lastLineMode(app)
 	} else if evk.Key() == tcell.KeyEscape {
 		gowid.SetFocusPath(mainview, menuPathMain, app)
 		gowid.SetFocusPath(altview1, menuPathAlt, app)